HIV/AIDS knowledge measures are widely used to determine the efficacy of HIV/AIDS prevention and education efforts. While much research has looked at the interventions, less attention has been paid to the quality of the measures themselves. Objectives: (a) To identify HIV/AIDS knowledge measures created for use with adults; (b) to determine the extent to which these measures have been psychometrically tested. Method: This article systematically reviews the use of psychometric testing of HIV/AIDS knowledge measures. Results: There has been minimal reliability and validity testing; of measures that had undergone some form of psychometric testing, 71% were created before the year 2000. Conclusion: More rigorous testing of these measures is critical to ensure they are appropriate for research, prevention, and practice. (Contains 4 tables and 1 figure.)